The modular units of the present invention are contemplated for shipment by tractor trailer or the like from the assembly plant. In this type shipment, the units must meet the width, height, length and weight limitations for the roadways on which they are to travel. Such limitations typically require the unit to be less than approximately fourteen (14) feet high, less than fourteen (14) feet wide and no greater than sixty (60) feet long. Under these limitations, a dormer or second story structure typically cannot be included during shipment as part of the module.
It is known to include a collapsible roof structure which is pivotally secured to the base module and which, when assembled, forms one-half of the A-frame roof. However, housing units having a second story which provide either a dormer type room or a complete second floor typically require a separate module to be added on top of the base unit. This results in shipments of multiple modules to complete a house. Also, typical second story modules include separate floor joists which rest on the ceiling joists of the base unit. Manifestly, the two joist structures are repetitive in defining the first and second floor and significantly add to the overall housing cost.